Molybdenum uses

First stainless steel lined swimming pools in France

The Vichy Water Sports Centre, located in France’s famous spa resort, was opened to the public in the summer of 2008, and is the first centre constructed in France equipped with 100% stainless steel pools. Chlorine content was a decisive factor in the choice of corrosion- resistant moly-grade materials. In addition to simple maintenance, stainless steel allowed the architect to use his imagination in shaping the pool’s design. Now, dozens of local communities have shown interest in using stainless steels to refurbish their pools.

The Bellerive-sur-Allier swimming pool, Vichy. It was the first Olympic-size swimming pool in France ever to be built of stainless steel. Photo: Jacques Rougerie.

Nearly 40 years ago Austria opened its first all stainless steel swimming pool. Since it was first filled with water, it hasn’t needed any refurbishment. Now France is following suit, opting for the innovative, economical and sustainable solution offered by stainless steel for the renovation and construction of its water sports centres. After the refurbishment of a pool for the commune of Saint Bonnet de Mure, Rhône in March 2008, the city of Vichy opened a new outdoor Olympic-size swimming pool, along with indoor amusement, learning and wading pools. In total, 2,150 square metres (23,142 square feet) of water surface are enclosed by more than 65 tonnes of stainless steel. The stainless steel is made of about 70% recycled material. Moly-grade austenitic stainless steels were chosen for their superior corrosion resistance in the chlorine-rich environment. The walls and bottoms of the pools and areas exposed to splashing or warm indoor humidity, such as handrails and ladders or the amusement pool’s slides, are all made from Type 316 stainless steel, supplied by ArcelorMittal.

Vibration of light

Architects have long been interested in using stainless steels in swimming pools, but it was the change in swimming pool material regulations that finally enabled these first two projects to move ahead in France. Jacques Rougerie, designer of the Vichy pools, heads a practice specializing in futuristic marine architecture, and water- related design is clearly his vocation. His commitment is almost lyrical: “Stainless steel contributes to setting a new scene with its “vibration of light” phenomenon that enables us to rethink the design of the place itself. It provides colour and expression like no concrete swimming pool can. For an architect, this is fabulous! For example, we capped the indoor pool with a blue-tinted polycarbonate dome that is reflected on the submerged metal surfaces, thus giving swimmers a sensation of incomparable weightlessness. Stainless steel also provides more flexibility in imagining highly varied forms.”

The Bellerive-sur-Allier swimming pool, Vichy. The stainless steel lining allows the designer to create complex shapes that are difficult to realize with other building materials.
Photo: Jacques Rougerie.

A giant pot

But a solid and rational technical argument follows immediately: “All pools have leakage problems. With a stainless steel pool, the water is contained much like water in a cooking pot! Furthermore, project execution is much simpler and shorter than with traditional tiled concrete. Finally, the gain in terms of sustainable development is incontestable: a hygienic, ecological (recyclable) material that requires less maintenance than conventional solutions, and is much longer-lasting.” But the architect knows how to be modest: “It is the advice and recommendations of the pool manufacturer that convinced me of the advantages of the material.” Since the inauguration, dozens of French local authorities have expressed an interest in using stainless steels in swimming pools, both for renovations and for new projects.